On Thu, Jan 31, 2002 at 01:03:33AM -0800, Thomas Bushnell, BSG wrote: > A race should always be avoided if it makes a bug. But there may be a > way to avoid it without select.
Well, the only other idea I have beside io_select would be to have another look just around the io_write that can be used to synchronize all pending_output_size operations with potentially blocking writes. Which means that a pending_output_size could block for a long time (just not on the global lock). Not too sexy in my eyes. So we should declare it as a non-bug ;) > pending_output_size is always approximate. Users cannot rely on it > being totally synchronized. The situation you describe here occurs > for almost all serial hardware in existence, and it's not a reason to > worry about anything else. So this case is a sort of race, but it's > not a bug, because we don't actually need to worry about the exact > value. Ok. Now, you avoided to answer what is the better approximation in case the underlying file supports tiocoutq. npending_output, the queue_size returned by tiocoutq, or the sum of both? > > Now, after the signature, an excerpt from the current implementation of the > > writer loop. What do you think? > > Looks reasonable to me. I assume that this function is the only one > that mucks with the pending_output array? Yes. The only variable in it that needs to be a static global is npending_output, output_stopped and hurdio_writer_condition (IIRC). Thanks, Marcus -- `Rhubarb is no Egyptian god.' Debian http://www.debian.org [EMAIL PROTECTED] Marcus Brinkmann GNU http://www.gnu.org [EMAIL PROTECTED] [EMAIL PROTECTED] http://www.marcus-brinkmann.de _______________________________________________ Bug-hurd mailing list [EMAIL PROTECTED] http://mail.gnu.org/mailman/listinfo/bug-hurd
